Ok, I've had SA running for several months and am soon going to set up a new Exchange server. Now I can't find the setting to change the email server that SA relays email off to. (btw, Ubuntu 12.04, SA 3.003002)

In the /etc/postfix/transport file, there are two entries for the current email server. (I don't know why there are two.)

I changed the first entry and commented out the second, restarted postfix but the messages are still going to the original server. [have rebooted it now, just to be sure.]

I did change it to smtp yesterday, no difference. But now I may have a deeper issue. Where does SA, or Ubuntu, look for DNS resolution?

I have three Windows DNS servers and the one I want to take down tomorrow is one of them. To test, I turned off DNS services on it last night and suddenly SA quit passing email. The log was saying it couldn't find the blacklist servers (by name) so it couldn't complete the spam test. We had no outside email since yesterday afternoon when I turned DNS off on that server.

So, if I take that server down completely I'm going to have a real problem if I can't tell SA where to find another DNS server.